Neuropsychologic Outcomes in a Case Series of Twins Discordant for Perinatal Stroke

from Pediatric Neurology

Perinatal stroke may affect cognitive development, but few studies have addressed the details of cognitive function after perinatal stroke. The present study was designed to compare the neuropsychologic features of five sets of twins discordant for perinatal stroke. All of the affected children had unilateral middle cerebral artery infarction (two left, three right); four of the five infarcts were large-branch, affecting the entire M1 territory. Three of the five affected children had comorbid epilepsy. Measures of intelligence, memory, language, attention, executive function, visual-motor integration, and fine motor skills were administered to children at a median age of 5 years (range, 5-8 years). Relative to their unaffected co-twins, the twins with perinatal stroke exhibited lower levels of full scale (p = 0.005), verbal (p = 0.006), and nonverbal (p = 0.005) intelligence. Children with perinatal stroke also showed significant deficits on tests of verbal memory (p = 0.041), receptive language (p = 0.011), verbal fluency (p = 0.019), and visual attention (p = 0.011), compared with their unaffected co-twins. Twin gestation may be a risk factor for poor cognitive outcome after perinatal stroke. Large infarct size and comorbid epilepsy may have contributed to some of the poor cognitive outcomes in this cohort.

The count-mass distinction in typically developing and grammatically specifically language impaired children: New evidence on the role of syntax and semantics

from the Journal of Communication Disorders

By the age of three, typically developing children can draw conceptual distinctions between “kinds of individual” and “kinds of stuff” on the basis of syntactic structures. They differ from adults only in the extent to which syntactic knowledge can be over-ridden by semantic properties of the referent. However, the relative roles of syntax and semantics in determining the nature of the count-mass distinction in language acquisition are still not well-understood. This paper contributes to this debate by studying novel noun acquisition in a subgroup of children, aged 8–15 years, with specific language impairment, whose core deficits are limited to within the grammatical system (G-SLI), We conducted two experiments: a production task and a word extension task. Such children might be expected to rely to a greater extent than their age-matched peers on semantic properties of referents in order to assign noun interpretations, since by hypothesis they have greater difficulty in accessing and utilizing syntactic category distinctions than typically developing children. In the production task, the Children with G-SLI demonstrated rigid over-application of a pluralization rule which masked even basic knowledge of semantic information about individuated objects versus non-individuated substances. Age-matched control children only performed in this way when all syntactic and conceptual/perceptual cues were neutralized. In the word extension task, which required a non-verbal response, the Children with G-SLI showed evidence of only very limited abilities to use syntactic or semantic information for word-learning. Thus, developmental deficits in the grammatical system can be seen to impact on lexical acquisition as well as syntactic development.

Functional localization of auditory cortical fields of human: Click-train stimulation

from Hearing Research

Averaged auditory evoked potentials (AEPs) to bilaterally presented 100 Hz click trains were recorded from multiple sites simultaneously within Heschl’s gyrus (HG) and on the posterolateral surface of the superior temporal gyrus (STG) in epilepsy-surgery patients. Three auditory fields were identified based on AEP waveforms and their distribution. Primary (core) auditory cortex was localized to posteromedial HG. Here the AEP was characterized by a robust polyphasic low-frequency field potential having a short onset latency and on which was superimposed a smaller frequency-following response to the click train. Core AEPs exhibited the lowest response threshold and highest response amplitude at one HG site with threshold rising and amplitude declining systematically on either side of it. The AEPs recorded anterolateral to the core, if present, were typically of low amplitude, with little or no evidence of short-latency waves or the frequency-following response that characterized core AEPs. We suggest that this area is part of a lateral auditory belt system. Robust AEPs, with waveforms demonstrably different from those of the core or lateral belt, were localized to the posterolateral surface of the STG and conform to previously described field PLST.

The maturation of human evoked brain potentials to sounds presented at different stimulus rates

from Hearing Research

The current study assessed the normal development of cortical auditory evoked potentials (CAEPs) in humans presented with pure tone stimuli at relatively fast stimulus rates. Traditionally, maturation of sound processing indexed by CAEPs has been studied in paradigms using inter-stimulus intervals (ISIs) generally slower than 1 Hz. While long ISIs may enhance the amplitude of CAEP components, speech information generally occurs at more rapid rates. These slower rates of sound presentation may not accurately assess auditory cortical functions in more realistic sound environments. We examined the effect of temporal rate on the elicitation of the P1–N1–P2–N2 components to unattended sounds at four levels of stimulus onset asynchrony (SOA, onset to onset, 200, 400, 600, and 800 ms) in children grouped separately by year (ages 8, 9, 10, 11 years), in adolescents (age 16 years) and in one group of young adults (ages 22–40 years). We found that both age and stimulus rate produced profound changes in CAEP morphology. Between the ages of 8–11 years, the P1 and N2 components dominated the ERP waveform at all stimulus rates. N1, the dominant CAEP component in adults, appeared as a bifurcation in a broad positive peak at earlier ages, and did not emerge as a separate component until adolescence. While the P1–N1–P2 components are more “adult-like” than “child-like” in the adolescent subjects, the N2 component, a hallmark of the child obligatory response, was still present. Faster rates resulted in the suppression of discrete components such that by 200 ms, only P1 in the adults and adolescents, and both P1 and N2 in the youngest children were discernable. We conclude that both age and ISI are important variables in the assessment of auditory cortex function and maturation. The presence of N2 in adolescents indicates that auditory cortical maturation persists into teen years.

OTOPod Wireless Diagnostic Audiometer

from MedGadget.com

Though marketed as being wireless, there are obviously cables that work with this new audiometer from Otovation of King of Prussia, PA. The convenience comes from not having to plug the unit into a computer, which makes it highly portable and provides more freedom for movement and positioning.

The device’s small size and elegant form combined with wireless operation make it convenient to use for both the hearing care professional and the patient.
The OTOPod is also great for use outside the office in patient settings, where the comfortable handheld unit with integrated patient response button is ideal.

Plus, the OTOPod can be used with a variety of transducers, including TDH-39, EAR 5A inserts, and Sennheiser circumaurals. The tranducers connect to the OTOPod with a mini-DIN connector for a nice secure connection.

Increased midsagittal tongue velocity as indication of articulatory compensation in patients with lateral partial glossectomies

from Head and Neck

Abstract

Background
The purpose of this study was to describe the impact of partial lateral glossectomy on midsagittal tongue movement during speech.

Methods
Using B-mode ultrasound, the midsagittal tongue movement of 10 patients with lateral partial glossectomy during a standardized reading passage was analyzed before and after surgery. Six normal adults served as control speakers. The main outcome measure was the tongue velocity during speech. The technique of defect reconstruction (local vs flap) was included as a covariate in the analysis.

Results
Following the surgery, all patients significantly increased the velocity of the midsagittal tongue movements during the reading passage.

Conclusion
The results demonstrated that the patients with partial glossectomy compensated for the lateral tongue resections by increasing the velocity of the residual tongue during speech. The study provides first insights into the biomechanical aspects of spontaneous articulatory compensation following lateral tongue resections. © 2008 Wiley Periodicals, Inc. Head Neck, 2008

Investigation of tracheoesophageal voice prosthesis leakage patterns: Patient’s self-report versus clinician’s confirmation

from Head and Neck

Abstract

Background
This study investigated the patient’s self-report and clinician’s confirmation of tracheoesophageal voice prosthesis leakage patterns (through or around) with or without the cough reflex and whether prosthesis diameter affected the leakage route.

Methods
Sixty-six consecutive participants with a total of 200 patient-initiated reasons for prosthesis changes were enrolled prospectively. Patient’s self-report of leakage and cough reflex were recorded prior to clinician’s confirmation.

Results
One-hundred eight (54%) of the 200 patient-initiated reasons for prosthesis changes were leakage through or around the voice prosthesis. Leakage was unrecognized in 21 (23%) of 92 instances, even though 15 (71%) of those 21 instances exhibited a cough reflex. Clinician’s confirmed leakage in 118 (59%) of 200 patient-initiated reasons for prosthesis changes. Coughing occurred significantly less with leakage around (9 [53%] of 17 instances) than that with leakage through the voice prosthesis (80 [88%] of 91 instances) (2 [1, N = 108], p < .05). Leakage around the voice prosthesis occurred more with 20-Fr diameter prostheses (16 [76%] of 21 instances).

Conclusions
Patient education is important for reliable identification of leakage for prompt prosthesis replacement. Leakage around the voice prosthesis can be minimized or avoided by initially fitting and continuing the use of smaller diameter (16 Fr) voice prostheses. © 2008 Wiley Periodicals, Inc. Head Neck, 2008

The logic of indirect speech

from the Proceedings of the National Academy of Sciences of the United States of America

When people speak, they often insinuate their intent indirectly rather than stating it as a bald proposition. Examples include sexual come-ons, veiled threats, polite requests, and concealed bribes. We propose a three-part theory of indirect speech, based on the idea that human communication involves a mixture of cooperation and conflict. First, indirect requests allow for plausible deniability, in which a cooperative listener can accept the request, but an uncooperative one cannot react adversarially to it. This intuition is supported by a game-theoretic model that predicts the costs and benefits to a speaker of direct and indirect requests. Second, language has two functions: to convey information and to negotiate the type of relationship holding between speaker and hearer (in particular, dominance, communality, or reciprocity). The emotional costs of a mismatch in the assumed relationship type can create a need for plausible deniability and, thereby, select for indirectness even when there are no tangible costs. Third, people perceive language as a digital medium, which allows a sentence to generate common knowledge, to propagate a message with high fidelity, and to serve as a reference point in coordination games. This feature makes an indirect request qualitatively different from a direct one even when the speaker and listener can infer each other’s intentions with high confidence.

Durable effects of concentrated disadvantage on verbal ability among African-American children

from the Proceedings of the National Academy of Sciences of the United States of America

Disparities in verbal ability, a major predictor of later life outcomes, have generated widespread debate, but few studies have been able to isolate neighborhood-level causes in a developmentally and ecologically appropriate way. This study presents longitudinal evidence from a large-scale study of >2,000 children ages 6–12 living in Chicago, along with their caretakers, who were followed wherever they moved in the U.S. for up to 7 years. African-American children are exposed in such disproportionate numbers to concentrated disadvantage that white and Latino children cannot be reliably compared, calling into question traditional research strategies assuming common points of overlap in ecological risk. We therefore focus on trajectories of verbal ability among African-American children, extending recently developed counterfactual methods for time-varying causes and outcomes to adjust for a wide range of predictors of selection into and out of neighborhoods. The results indicate that living in a severely disadvantaged neighborhood reduces the later verbal ability of black children on average by 4 points, a magnitude that rivals missing a year or more of schooling.

Modelling relations between sensory processing, speech perception, orthographic and phonological ability, and literacy achievement

from Brain and Language

The general magnocellular theory postulates that dyslexia is the consequence of a multimodal deficit in the processing of transient and dynamic stimuli. In the auditory modality, this deficit has been hypothesized to interfere with accurate speech perception, and subsequently disrupt the development of phonological and later reading and spelling skills. In the visual modality, an analogous problem might interfere with literacy development by affecting orthographic skills. In this prospective longitudinal study, we tested dynamic auditory and visual processing, speech-in-noise perception, phonological ability and orthographic ability in 62 five-year-old preschool children. Predictive relations towards first grade reading and spelling measures were explored and the validity of the global magnocellular model was evaluated using causal path analysis. In particular, we demonstrated that dynamic auditory processing was related to speech perception, which itself was related to phonological awareness. Similarly, dynamic visual processing was related to orthographic ability. Subsequently, phonological awareness, orthographic ability and verbal short-term memory were unique predictors of reading and spelling development.